A conventional photosensitive body installed in a process cartridge detachable relative to a main frame of an image forming device such as a copying machine, printer, and facsimile is generally in the form of a cylindrical shape having a small diameter. The photosensitive body includes a cylindrical electrically conductive photosensitive drum, an electrically conductive shaft rotatably supporting the photosensitive drum, and an electrically conductive contact member.
The photosensitive drum includes a drum body (aluminum tube) whose outer surface is formed with a photosensitive layer. Further, an end flange is fitted at each end of the aluminum tube. The shaft extends through a radial center of each flange. One of the flanges is provided with a gear for drivingly rotating the photosensitive body about its axis.
In such conventional photosensitive body, the end flange is made from a synthetic resin in view of reduction in weight and cost. Here, in the electro-photographic process, the drum body must be electrically connected to the main frame because of the necessity of grounding. To this effect, the contact member such as an electrically conductive plate (grounding plate) is provided for electrical connection between the shaft and the drum body.
More specifically, the electrically conductive plate has generally disk shape and is forth-fitted with inner peripheral side of the end portion of the drum body along with the end flange. The electrically conductive disk plate has an outer peripheral portion provided with a protrusion adapted to be in contact with the drum body, and has a radially center portion formed with a through-hole through which the shaft extends. The electrically conductive disk plate has a reed like contact portion that is in resilient contact with an outer peripheral surface of the shaft extending through the through-hole. Such conventional arrangement is described in laid open Japanese Patent Application Publication No. H10-207291, 2002-91234, 2004-102270, and 2006-72039.